Re: [PATCH v3 4/4] hwmon: Support Aspeed AST2600 PWM/Fan tachometer

["Andrew Jeffery" <andrew@aj.id.au>]

On Wed, 20 Jan 2021, at 15:53, Ryan Chen wrote:
> > -----Original Message-----
> > From: Andrew Jeffery <andrew@aj.id.au>
> > Sent: Wednesday, January 20, 2021 1:16 PM
> > To: Troy Lee <troy_lee@aspeedtech.com>; openbmc@lists.ozlabs.org; Joel
> > Stanley <joel@jms.id.au>; Philipp Zabel <p.zabel@pengutronix.de>; open list
> > <linux-kernel@vger.kernel.org>; moderated list:ARM/ASPEED MACHINE
> > SUPPORT <linux-arm-kernel@lists.infradead.org>; moderated
> > list:ARM/ASPEED MACHINE SUPPORT <linux-aspeed@lists.ozlabs.org>
> > Cc: Ryan Chen <ryan_chen@aspeedtech.com>; ChiaWei Wang
> > <chiawei_wang@aspeedtech.com>; Troy Lee <leetroy@gmail.com>; kbuild
> > test robot <lkp@intel.com>
> > Subject: Re: [PATCH v3 4/4] hwmon: Support Aspeed AST2600 PWM/Fan
> > tachometer
> > 
> > Hi Troy,
> > 
> > On Mon, 18 Jan 2021, at 17:20, Troy Lee wrote:
> > > Add Aspeed AST2600 PWM/Fan tacho driver. AST2600 has 16 PWM channel
> > > and
> > > 16 FAN tacho channel.
> > >
> > > Changes since v2:
> > >  - declare local function as static function
> > >
> > > Changes since v1:
> > >  - fixed review comments
> > >  - fixed double-looped calculation of div_h and div_l
> > >  - moving configuration to device tree
> > >  - register hwmon driver with devm_hwmon_device_register_with_info()
> > >
> > > Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
> > > Reported-by: kernel test robot <lkp@intel.com>
> > > ---
> > >  drivers/hwmon/Kconfig                |  10 +
> > >  drivers/hwmon/Makefile               |   1 +
> > >  drivers/hwmon/aspeed2600-pwm-tacho.c | 756
> > > +++++++++++++++++++++++++++
> > >  3 files changed, 767 insertions(+)
> > >  create mode 100644 drivers/hwmon/aspeed2600-pwm-tacho.c
> > 
> > ...
> > 
> > > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index
> > > 09a86c5e1d29..1a415d493ffc 100644
> > > --- a/drivers/hwmon/Makefile
> > > +++ b/drivers/hwmon/Makefile
> > > @@ -52,6 +52,7 @@ obj-$(CONFIG_SENSORS_ARM_SCPI)	+=
> > scpi-hwmon.o
> > >  obj-$(CONFIG_SENSORS_AS370)	+= as370-hwmon.o
> > >  obj-$(CONFIG_SENSORS_ASC7621)	+= asc7621.o
> > >  obj-$(CONFIG_SENSORS_ASPEED)	+= aspeed-pwm-tacho.o
> > > +obj-$(CONFIG_SENSORS_ASPEED2600_PWM_TACHO)	+=
> > aspeed2600-pwm-tacho.o
> > 
> > Why does this have to be a separate implementation from the existing ASPEED
> > PWM/Tacho driver? Is there really nothing in common?
> > 
> Hello Andrew,
> 	The register set is fully re-arrange. And it is new design at AST2600, 
> can't be compatible with older PWM.  
>

Ah, okay. I hadn't looked. Thanks Ryan.

Andrew